Lumped parameter circulator and its construction



, y 1970 TADA SHI HASH'IMOTO ET AL 3,510,804

LUMPED PARAMETER CIRCULATOR AND ITS CONSTRUCTION Filed May 29. 1968 PRIOR ART m 5 mm m m H WMAMJ Rv 5 H 2 MW 3 f l H 3 4 mo a; g RUM H F @wm United States Patent Office 3,510,804 Patented May 5, 1970 3,510,804 LUMPED PARAMETER CIRCULATOR AND ITS CONSTRUCTION Tadashi Hashimoto, Ichikawa, Chiba-ken, Taro Miura,

Tokyo, and Takashi Iwata, Ichikawa, Chiba-ken, Japan,

assignors to TDK Electronics Company Limited, Tokyo,

Japan, a corporation of Japan Filed May 29, 1968, Ser. No. 732,934 Int. Cl. H01p 1/32 U.S. Cl. 3331.1 2 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to an improvement in Y-type lumped parameter circulators. The circulator of the invention comprises a plurality of central conductors assembled in a knitted construction; disk shaped magnets arranged both above and below the surfaces of said central conductors as a means for effecting circulator action; a shielding case arranged so as to envelope said central conductors and magnets, said shielding case having an upper surface portion of true hexagonal shape and side plates provided at every other side periphery of said upper surface portion, said depending side plates being provided with hollow cuts at each side periphery thereof for passing the centrol conductors therethrough; and an assembly base plate having linear slits; said side plates of the shielding case being passed through said linear slits and folded at their tips behind said assembly base plate, and said central conductors being received in said hollow cuts of the side plates of the shielding case. By utilization of the above structure and arrangement, assembly steps of the unit are simplified. The central conductors employed may be optionally coated with an insulating layer at their mutual points of contact.

This invention relates to an improvement in Y-type lumped parameter circulators.

In lumped parameter circulators, it has been required to provide a shielding case for shielding of the magnetic members effecting circulator action, for the purpose of avoiding any radiation of electromagnetic waves out of the magnetic members and forming an outer conductor.

Generally, magnetic members in the form of disk shape are used to effect circulator action and, hence, a type of shielding case such as shown in FIG. 1A of the accompanying drawings is utilized, for performing the shielding of the magnetic members. However, the use of a shielding case of the type shown not only results in high industrial manufacturing costs, but also causes noticeable inconveniense in treating. The present invention eliminated the above defects of the conventional lumped parameter circulators.

It is a further object of the present invention to provide a circulator which is manufactured and assembled in an improved and easier manner.

The present invention shall now be described in detail with reference to the accompanying drawing, in which:

FIG. 1A shows a conventional shielding case.

FIG. 1B shows a shielding case of the present invention.

FIG. 2 shows a perspective view of a Y-type lumped parameter circulator utilizing the shielding case of the present invention, with its respective parts disassembled.

FIG. 3 shows central conductors arranged in a typical manner such as used in the Y-type lumped parameter circulator.

FIG. 4A shows one of the central conductor elements to be used in another embodiment of the present invention.

FIG. 4B shows the relation between the central conductors such as shown in FIG. 4A and the shielding case shown in FIG. 113 as assembled, the shielding case being in fragmentary section.

While the present invention will be explained with reference to preferred embodiments of the invention as illustrated, it should be appreciated that the invention is not intended to be restricted to the particular embodiments disclosed and illustrated, but is rather intended to cover any possible alterations, modifications and equivalent arrangements falling within the spirit and the scope of the invention.

Referring now to the drawings, and more particular to FIG. 1B, 1 is the upper surface portion of a shielding case made from a metal plate of a non-magnetic material, which portion is formed in a true hexagonal shape and is provided at its every other periphery with side plates 2, 3 and 4 having hollow cuts 5 and 5' provided at both side peripheries of the vertically depending side plates for passing legs of the central conductors therethrough.

According to the present invention and as shown in FIG. 2, the upper surface portion 1 of the shielding case is formed in a true hexagonal shape and the side plates 2, 3 and 4 are provided therewith, as described above. Thus, the portions of said side plates engaging with an assembly base plate '6 would naturally be linear and, hence, it becomes possible to mount the shielding case to the assembly base plate 6 in an extremely simply manner by providing linear slits 7, 8 and 9 in the assembly base plate 6 in a relation to their respective axial lines extended, passing the side plates of the shielding case through these linear slits, and folding inward or outward said side plates at the sections protruding through the base plate, said sections being indicated with broken lines in FIG. 2.

As further shown in FIG. 2, 10 and 10 are magnetic members of disk shape and 11, 12 and 13 are central conductors. The disk shaped magnetic members 10 and 10" are arranged above and below said conductors 11, 12 and 13.

In the particular lumped parameter circulator shown, the central conductors 11, 12 and 13 are formed in a U-shape, and are arranged so their axial lines deviate from each other by 120".

In such case in which triple symmetry is not required in the isolator, the central conductors may be simply superposed through an isolating plate therebetween, but in the same angular relation as that described in the above. In this particular case, the assembly operation of the isolator will be remarkably effectively simplified by utilizing a set of central conductors 14, an example of which is illustrated in FIG. 4A, in combination with the shielding case of the present invention. That is, as shown in FIG. 4B, the central conductors 14 are formed in such a manner that the free ends of the leg portions of the conductors 11, 12 and 13 of FIG. 2 are connected with each other and, thus, the positions of the respective conductors 14 can be easily set in the predetermined sides of said connecting portions into close contact with" the outer surfaces side plates 2, 3 and 4 of the shielding of FIG. 1B so as to engage the adjacent leg portions of the conductors 14 with the hollow cuts 5 and 5 of the side plates 2, 3 and 4.

In addition, and in conjunction with the above mentioned embodiments of the invention, an insulating paint such as enamel or other insulating material may be applied to each of the central conductors at their mutual points of contact (the ends remaining uncoated), so that the assembly may be performed without using any other insulating plate. Therefore, in the assembly operation of the central conductors, the step of setting an insulating member between said central conductors can be eliminated and thus the manufacturing cost of the circulator will be effectively reduced.

What is claimed is:

1. A circulator comprising a plurality of central conductors assembled in a knitted construction; disk shaped magnets arranged both above and below the surfaces of said central conductors as a means for effecting circulator action; a shielding case arranged so as to envelop said central conductors and magnets, said shielding case having an upper surface portion of true hexagonal shape and depending side plates provided at every other side periphery of said'upper'surface'portion, said'depending side plates being provided with hollow cuts at each side periphery thereof for passing the central conductors therethrough; and an assembly base plate having linear slits; said side plates of the shielding case being passed through said linear slits and folded at their tips behind said assembly base plate, and said central conductors being received in said hollow cuts of the side plates of the shielding case.

2. The circulator according to claim 1, wherein said central conductors are coated with a thin layer of an insulating material at their mutual points of contact.

References Cited UNITED STATES PATENTS 2/1967 Weiss' 333l.1 8/1967 Konishi 333-11 US. Cl. X.R. 29600; 333-84 

